Seasonal incidence and effect of abiotic factors on population dynamics of major insect pests on brinjal crop

Abstract

Effect of abiotic factors on the seasonal incidence of major insect pests was observed on brinjal crop during Rabi 2009. The incidence of leaf hopper (Amrasca biguttula biguttula) was maximum during December, 52 nd Standard Week (SW) and minimum during March (12 th SW). The incidence of white fly (Bemisia tabaci) was maximum during January (2 nd SW) and lowest in March (12 th SW). Both these insects showed significant negative correlation with both maximum and minimum temperature and wind speed while a positive correlation was revealed with mean relative humidity and total rainfall. The incidence of shoot and fruit borer, Leucinodes orbonalis Guenee was observed during Nov. -Dec. with peak infestation during Feb. (6 th and 7 th SW). The per cent shoot damage was positively correlated with both maximum and minimum temperature, rainfall and wind speed while negatively correlated with mean relative humidity. While per cent fruit infestation revealed a non significant positive correlation with maximum and minimum temperature, rainfall and wind speed exhibited negative correlation with mean relative humidity. The statistically significant values indicated that occurrence of insect pests population was due to the prevailing ecological conditions. Thus the management of brinjal pest complex during Rabi sown brinjal should therefore be promoted and tailored from November onwards using an integrated approach.How to view point the article : Indirakumar, K., Devi, M. and Loganthan, R. (2016). Seasonal incidence and effect of abiotic factors on population dynamics of major insect pests on brinjal crop Internat. J. Plant Protec., 9(1) : 142-145.

Role of Weather Parameters on Population Build Up of Minor Insect Pests of Brinjal

“…When the different meteorological parameters were correlated (Table .3) with the population buildup of A. biguttula biguttula, it was observed that maximum temperature (r= 0.560) showed a significant positive correlation whereas minimum temperature (r= 0.414), total rainfall (r = 0.087) and bright sunshine hour (r = 0.296) also showed a nonsignificant positive correlation with leaf hopper population whereas average relative humidity (r= -0.331) showed a negative association with leafhopper. It was also indicated negative correlation with maximum and minimum temperature and positive correlation with rainfall as reported by a Chandrakumar et al, (2008) and Indirakumar et al, (2016), respectively. Prasad and Logiswaram (1997) also reported significant positive association with maximum temperature and negative association with rainfall.…”

Comprehensive Review on the Bio-ecology and Integrated Management Strategies for Brinjal Shoot and Fruit Borer (Leucinodes orbonalis Guenee)

“…arvense L.) [12], Dark nightshade (S. nigrum L.), Turkey berry (S. torvum Swartz) [33], and Gilo (S. gilo Raddi). The wild hosts of L. orbonalis include Black nightshade (S. anomalum Thonn) [101], African eggplant (S. macrocarpon L.) [48], Tropical Soda Apple (S. viarum Dunal), Indian nightshade or Kantakari (S. xanthocarpumSchrad), Cape ooseberry (Physalis peruviana L.), Pygmy groundcherry (Physalis minima L.), and Forest Bitter Berry (Solanum anguiviLam.) [28].…”

“…Their findings have shown that the biophysical characteristics of shoot and fruit borer insect populations are reduced, as shown in Table 2. Polyphenol oxidase (PPO), Phenylalanine ammonium lyase (PAL) and Lignin [48] Pubescent types characterized by dense and lengthy upright hairs on their surface obstruct adult insects from laying eggs and hatching them.…”

Seasonal Incidence of Insect Pests of Tomato (Lycopersicum esculentum Miller)

“…The present data was in accordance with Kumar et al [11] who revealed that the population reached peak in second week of March. However, Dhatonde et al [12] and Indirakumar et al [13] reported the peak population of whitefly during the month of January. This finding contradicts with the present results.…”

“…temperature and a significant negative correlation with morning and evening relative humidity. Indrakumar et al [13] Dhaka and Pareek [14] Shahnaz et al [15] who reported a significant positive correlation with max. and min.…”